Visualizations of water quality across the conterminous United States using SPARROW 2012 simulated nutrient load estimates

This pipeline uses the data from the 2012 regional Sparrow models (see **Input datasets** below) to produce four types of outputs:

1. Maps of SPARROW-estimated total nitrogen, total phosphorus, and total suspended-sediment yields and concentrations across the conterminous United States (CONUS);
2. Bar plots showing the amount of total nitrogen, total phosphorus, and suspended sediment load generated within each of the 18 aggregated level 3 eco-regions that make up the CONUS, including the relative contribution from each source to the total regional load;
3. Maps showing a comparison between the SPARROW-estimated total nitrogen and total phosphorus concentrations and the EPA’s National Rivers and Streams Assessment (NRSA) benchmark nutrient concentrations within each aggregated level 3 eco-region; and
4. A data table that shows the reach-level stoichiometric ratio between the SPARROW-estimated total nitrogen and total phosphorus concentrations and a comparison between those concentrations and the applicable EPA benchmark nutrient concentration.